Stick that file, marking.bmp, and another one called marking_a.bmp into the texsrc folder. Marking_a.bmp should be sitting in your savedtex folder.
marking_a.bmp is an alpha mask, it doesn't need editing or anything, Neither does marking.bmp (unless you want too) This assumes you want to keep the Star and Bar. To get rid of it entirely make the marking_a.bmp file completely black and the stars will dissaper.
Alpha masks can be applied to any texture. They are very useful for removing some things. Just remember to save them as greyscale rather than 8bit colour.
Gatso